The Worldwide Interoperability for Microwave Access (WiMAX) is a radio metropolitan area network technology based on the IEEE 802.16 standard. As shown in FIG. 1a, the logic architecture of a WiMAX network includes three parts: Mobile Station System/Subscriber Station (MSS/SS), Access Service Network (ASN) and Connection Service Network (CSN), and includes logic entities such as Policy Flow (PF) server, Authentication Authorization Accounting (AAA) server, and Application Flow (AF) server. The Quality of Service (QoS) reference mode defined in the underway WiMAX standard draft is shown in FIG. 1b. 
The Service Flow Management (SFM) entity is located in the ASN and is responsible for admission control, creation, activation, modification and deletion of service flows. An SFM entity includes an Admission Control (AC) unit and a local resource database correlated to the AC. A Service Flow Authorization (SFA) entity is located in an ASN for the purpose of authenticating and authorizing the requested service flows. Each MS/SS corresponds to only one anchor SFA. The anchor SFA entity interacts with the Policy Flow (PF) server. The SFA directly interacting with the SFM is called a serving SFA. The serving SFA may be the same entity as the anchor SFA. If they are different entities, more than one SFA may exist between them for the purpose of handling primitives related to relay QoS. Such SFA entities are called relay SFAs. A serving SFA and an anchor SFA must be aware of each other anytime. The anchor SFA executes policy management of the ASN level according to the Local Policy Database (LPD). An AF server is located in a home Network Service Provider (NSP). The MS/SS interacts with the AF directly through an application-layer protocol. An AF server may send a WiMAX service flow request to the PF server directly in order to trigger the PF server to send a Resource Reservation Request (RR-Request) to the ASN. A PF server is a policy service entity located in a home NSP. The entity related to the PF server is a user database, which includes the service policies that allow access and the corresponding preset QoS parameters.
Dynamic Service flow Addition (DSA) refers to creation of an application service flow initiated at the subscriber side. FIG. 2a shows the process of creating a dynamic service flow according to the existing standard draft. As shown in FIG. 2a, a Dynamic Service flow Addition Request (DSA-Request) sent by the Mobile Station (MS) triggers only the network-side policy decision process (PD-Request/Response). A Dynamic Service flow Addition Response (DSA-Response) is returned upon completion of the policy decision process. The creation of an air interface (R1 interface) is completed when the MS returns a Dynamic Service flow Addition Acknowledgement (DSA-ACK). At this time, the MS is ready to send data. However, the policy decision process defined by the existing standard draft executes only the admission process. Namely, after this process, the network side tells the MS only about the readiness of meeting the resource requirement (QoS requirement) of the MS. However, the network side neither allocates a Service Flow ID (SFID) for identifying the service flow nor creates a data path for transmitting service flows. At this time, it is impossible to transmit the service of the MS at all.
As analyzed above, the Dynamic Service flow Addition (DSA) process specified in the existing standard draft is incomplete, and does not enable data transmission; moreover, the existing standard draft specifies no detailed process of changing or deleting dynamic service flows.
Creation of a network-side service flow includes creation of a preset flow and creation of other network-side application service flows. The common feature is that the creation of service flows is initiated by the network side, and oriented to the user. FIG. 2b shows the process of creating a service flow at the network side according to the existing standard draft.
The process of creating a service flow at the network side is implemented by a Resource Reservation (RR) message. The corresponding air interface message is a dynamic service flow addition message (DSA-Request/Response/Acknowledge). However, after the creation process is completed, only an air interface connection is created, the data path in the ASN is not created, and the service cannot be transmitted normally.
As analyzed above, the process of creating a network-side service flow specified in the existing standard draft is incomplete, and does not enable data transmission; moreover, the existing standard draft specifies no detailed process of changing or deleting network-side service flows.